FIELD OF THE INVENTION
The field of this invention relates to copolyimides prepared from mixtures of tetramethylcyclobutane-1,2,3,4-tetracarboxylic dianhydride (TMCDA) and aromatic or aliphatic dianhydrides. These dianhydride mixtures are then reacted with aliphatic or aromatic diamines. These novel copolyimides are useful in the preparation of molded articles, fibers, films, laminates and coatings.